Park E, Park J, Han SW, Im SA, Kim TY, Oh DY, Bang YJ

Park E, Park J, Han SW, Im SA, Kim TY, Oh DY, Bang YJ. RAF and STAT3 inhibitors is an effective therapy for treating lung cancer cells harboring KRAS mutations. Taken together, the current results indicate that oncogene dependency can be targeted for therapy in lung cancer cells harboring RAS-mutant. and xenograft mice models confirmed this finding. In addition, though this combination or single agent significantly caused the apoptosis of both KRAS mutant cancer cells and wild-type cells, it is observed that the two inhibitors combination obviously enhanced the ability of apoptosis induction in lung cancer cells harboring KRAS mutation, indicating the combination of RAF and STAT3 inhibitors is an effective therapy for treating lung cancer cells harboring KRAS mutations. RESULTS KRAS-mutant lung cancer cells are selectively sensitive to the combined inhibition of RAF and STAT3 AZ628 is one of the inhibitors of RAF, and BP-1-102 is usually a STAT3 inhibitor. To evaluate the therapeutic effect of combined AZ628 and BP-1-102 on lung cancer cells, we analyzed the conversation (synergistic, additive or antagonistic) by calculating the combination index (CI). CI 0.7 is considered as synergism; CI = 0.7C0.9 is moderate synergism; CI = 0.90C1.10 is nearly additive; and CI 1.10 is antagonism. The cytotoxicity of combined AZ628 and BP-1-102 is usually enhanced in KRAS(G12D) H838 cells compared with KRAS(WT) H838 cells, and the CI values were 0.7 in all groups with different concentrations combination, suggesting a strongly synergistic conversation between AZ628 and BP-1-102 in KRAS mutant lung cancer cells (Determine 1). In KRAS(G12S) H292 and KRAS(G12V) H441 cells which had KRAS mutation, the combination showed obvious synergism in some concentrations, whereas in other concentrations the drug effect was nearly additive. In contrast, antagonistic conversation between this combination drugs was observed in H661 and H1650 cells which were KRAS wild-type lung cancer cells. These findings indicated that KRAS mutant lung cancer cells might be selectively sensitive to combined AZ628 and BP-1-102. Open in a separate window Physique 1 The combination of AZ628 and BP-1-102 showed a strongly synergistic conversation in KRAS-mutant lung cancer cells. Relative viability was measured for KRAS(WT) H838 and KRAS(G12D) H838 cells (A), KRAS(G12S) H292 and KRAS(G12V) H441 cells (B), as well as KRAS(WT) H661and H1650 cells (C) that were treated with the single drug or combined drugs. CI values were calculated for cells treated with a combination of AZ 628 and BP-1-102. CI 0.7 is considered as synergism; CI = 0.7C0.9 is moderate synergism; CI = 0.90C1.10 is nearly additive; and CI 1.10 is antagonism. The combination of RAF and STAT3 inhibitors enhanced the inhibition of KRAS mutant lung cancer cells growth To confirm the synergistic effect of RAF and STAT3 inhibitors, we evaluated their functions in the growth of KRAS mutant lung cancer cells by using AZ628 (2 M) and BP-1-102 (10 M). The clonogenic assays revealed that in KRAS(G12D) H838 cells, this combination caused more enhanced inhibition effect on cell growth than either agent alone, whereas there is no significant difference in H838 cell growth (Physique 2A). The similarly enhanced inhibition effects of this combination were also observed in KRAS(G12V) H441 and KRAS(G12S) H292 cells (Physique 2B). In contrast, in KRAS(WT) H661and H1650 cells, the results showed no significant effect of combined AZ628 and BP-1-102 on cell growth (Physique 2C). Open in a separate window Physique 2 The combination of AZ628 and BP-1-102 enhanced the inhibition of KRAS mutant lung cancer cells growth. (A) Clonogenic assay was performed for KRAS(WT) H838 and KRAS(G12D) H838 cells treated with single or combination drugs. The statistical analysis was also exhibited. * p 0.05. **p 0.01. ***p 0.001. (B) Clonogenic assay was performed for KRAS(G12S) H292 and KRAS(G12V) H441 cells treated with single or combination drugs. The statistical analysis was also tested. * p 0.05. ***p 0.001. (C) Clonogenic assay was performed for KRAS(WT) H661and H1650 cells treated with single or combination drugs. The statistical analysis was also resolved. * p 0.05. **p 0.01. The combination of RAF and STAT3 inhibitors induced cell apoptosis increase Cell apoptosis assays were performed with single inhibitor or a combination of AZ628 and BP-1-102 on a panel of KRAS mutant lung cancer cells and wild-type lung cancer cells. The results showed that single BAY-876 inhibitor also owned the ability to induce cell apoptosis in both KRAS mutant lung cancer cells and wild-type lung cancer cells (Physique 3A). However, KRAS(G12D) H838, KRAS(G12V) H441 and KRAS(G12S) H292cells showed far higher apoptotic response to the combination than to single inhibitor compared with KRAS(WT) H838, H661and H1650 cells. Open in a separate windows Physique 3 The combination of AZ628 and BP-1-102 induced.CI 0.7 is considered as synergism; CI = 0.7C0.9 is moderate synergism; CI = 0.90C1.10 is nearly additive; and CI 1.10 is antagonism. the current results indicate that oncogene dependency can be targeted for therapy in lung cancer cells harboring RAS-mutant. and xenograft mice models confirmed this finding. In addition, though this combination or single agent significantly caused the apoptosis of both KRAS mutant cancer cells and wild-type cells, it is observed that the two inhibitors combination obviously enhanced the ability of apoptosis induction in lung cancer cells harboring KRAS mutation, indicating the combination of RAF and STAT3 inhibitors is an effective therapy for treating lung cancer cells harboring KRAS mutations. RESULTS KRAS-mutant lung cancer cells are selectively sensitive to the combined inhibition of RAF and STAT3 AZ628 is one of the inhibitors of RAF, and BP-1-102 is usually a STAT3 inhibitor. To BAY-876 evaluate the therapeutic effect of combined AZ628 and BP-1-102 on lung cancer cells, we analyzed the conversation (synergistic, additive or antagonistic) by calculating the combination index (CI). CI 0.7 is considered as synergism; CI = 0.7C0.9 is moderate synergism; CI = 0.90C1.10 is nearly additive; and CI 1.10 is antagonism. The cytotoxicity of combined AZ628 and BP-1-102 is usually enhanced in KRAS(G12D) H838 cells compared with KRAS(WT) H838 cells, and the CI values were 0.7 in all groups with different concentrations combination, suggesting a strongly synergistic conversation between AZ628 and BP-1-102 in KRAS mutant lung cancer cells (Determine 1). In KRAS(G12S) H292 and KRAS(G12V) H441 cells which had KRAS mutation, the combination showed obvious synergism in some concentrations, whereas in other concentrations the drug effect was nearly additive. In contrast, antagonistic interaction between this combination drugs was observed in H661 and H1650 cells which were KRAS wild-type lung cancer cells. These findings indicated that KRAS mutant lung cancer cells might be selectively sensitive to combined AZ628 and BP-1-102. Open in a separate window Figure 1 The combination of AZ628 and BP-1-102 showed BAY-876 a strongly synergistic interaction in KRAS-mutant lung cancer cells. Relative viability was measured for KRAS(WT) H838 and KRAS(G12D) H838 cells (A), KRAS(G12S) H292 and KRAS(G12V) H441 cells (B), as well as KRAS(WT) H661and H1650 cells (C) that were treated with the single drug or combined drugs. CI values were calculated for cells treated with a combination of AZ 628 and BP-1-102. CI 0.7 is considered as synergism; CI = 0.7C0.9 is moderate synergism; CI = 0.90C1.10 is nearly additive; and CI 1.10 is antagonism. The combination of RAF and STAT3 inhibitors enhanced the inhibition of KRAS mutant lung cancer cells growth To confirm the synergistic effect of RAF and STAT3 inhibitors, we evaluated their roles in the growth of KRAS mutant lung cancer cells by using AZ628 (2 M) and BP-1-102 (10 M). The clonogenic assays revealed that in KRAS(G12D) H838 cells, this combination caused more enhanced inhibition effect on cell growth than either agent alone, whereas there is no significant difference in H838 cell growth (Figure 2A). The similarly enhanced inhibition effects of this combination were also observed in KRAS(G12V) H441 and KRAS(G12S) H292 cells (Figure 2B). In contrast, in KRAS(WT) H661and H1650 cells, the results showed no significant effect of combined AZ628 and BP-1-102 on cell growth (Figure 2C). Open in a separate window Figure 2 The combination of AZ628 and BP-1-102 enhanced the inhibition of KRAS mutant lung cancer cells growth. (A) Clonogenic assay was performed for KRAS(WT) H838 and KRAS(G12D) H838 cells treated with single or combination drugs. The statistical analysis was also demonstrated. * p 0.05. **p 0.01. Rabbit Polyclonal to VRK3 ***p 0.001. (B) Clonogenic assay was performed for KRAS(G12S) H292 and KRAS(G12V) H441 cells treated with single or combination drugs. The statistical analysis was also tested. * p 0.05. ***p 0.001. (C) Clonogenic assay was performed for KRAS(WT) H661and H1650 cells treated with single or combination drugs. The statistical analysis.